Laminating method and means for manufacturing synthetic resinous foam pads



Feb. 6, 1962 LAWRENCE 3,020,186

LAMINATING METHOD AND MEANS FOR MANUFACTURING SYNTHETIC REsINoUs FOAM PADS Filed May 21, 1959 A@ A; F c of? /J/ United States Patent 3 020 186 LAMINATING METHD ND MEANS FOR MAN- UAITURING SYNTHETIC RESINOUS FOAM P D Leonard Lawrence, 118 84th Ave., Kew Gardens, N. Filed May 21, 1959, Ser. No. 814,780 2 Claims. (Cl. 156-248) This invention relates generally to the field of plastic lamination, and more particularly to an improved method and means for forming synthetic resinous foam pads, suitable for use as cushions, absorbent iiuid ev'aporators, and

the like. l

With the increased use of pressure-sensitive adhesives, in general, there Ihas been a tendency to make pads of the type described with such adhesives as the means for attaching the pad `to a Vplanar or other surface. This material has substituted for the older type of mucilage or glue which is normally moistened prior to application, and has the advantage of 4being more sanitary as well as more convenient to use. Unfortunately, while pressure-sensitive adhesives are relatively strong, and will resist a direct pull norm-al to the plane of adhesive interconnection, they -are subject to peeling or rubbing action exerted in a plane parallel to the plane of adhesive interconnection. Thus, when pads are employed, for example, as a means for relieving pressure upon a corn, the rubbing exerted by the sock of the user often disengages the pad from adhesive interconnection with the toe of the,

wearer, so that the effect of the pad is lost.

It is therefore among the principal objects of the present invention lto provide an improved synthetic resinous foam pad employing pressure-sensitive adhesives, in which the contour of pad resulting from an improved method of manufacture, has been altered so as to provide an absence of upstanding edges which may be caught or engaged in a sliding or rubbing movement of the surface to which the pad is adhesively attached.

Another object of the invention lies in the provision of a novel method for forming pads possessed of the above described advantage which permits the formation of a large number of such pads in a single operation in mounted position upon a display card or similar device suitable for immediate packaging, thereby reducing cost of fabrication to a very low order.

Still another object of the invention lies in the provision of an improved method for manufacturing synthetic resinous foam pads which is suitable for use over a wide variety of shapes and sizes of pads, whereby the invention has application to a wide variety of arts.

A feature of the invention lies in the fact that the manufacture of the inventive devices inthe mounting of the same upon a display card may be performed in a single simultaneous operation.

Another feature of the invention lies in the ease with which the completed pad may be detached from the card upon which the same are mounted at the completion of the fabricating step.

These objects and features, as well as other incidental ends and advantages, will more fully appear in the progress of the following disclosure, and be pointed out in the appended claims.

In the drawing, to which reference will be made in the specification, similar reference characters have been employed to designate vcorresponding parts throughout the several views.

FIGURE 1 is an exploded view in perspective showing a first step in the manufacture of the disclosed device.

FIGURE 2 is a vertical sectional view showing a second step in the manufacture of the disclosed article.

FIGURE 3 is a View in perspective showing a die used 2 in connection with the stamping and forming the manufacture of the disclosed article. p

FIGURE 4 is a transverse sectional view as seen from the plane 4-4 in FIGURE 3.

FIGURE 5 is a view in perspective showing a final step in the manufacture of the disclosed article.

FIGURE 6 isa view in perspective showing a plurality of completed articles mounted upon a display oard and ready for packaging.

FIGURE 7 is a view in perspective showing a pleted pad embodying the invention.

In accordance with the invention, the iirst step in the manufacture of pressure sensitive adhesive synthetic resinous foam pads contemplated by the invent-ion consistsin the provision of a fibrous base, generally indicated by reference character 13 having at least an upper surface 14 thereof which is parchmentized and smoothly calendered to permit a pressure sensitive adhesive to be readily stripped therefrom. A planar sheet 16 of polyvinyl acetate, or vinyl copolymer is next provided, having an upper surface 17, and a lower surface 18, the latter of which is provided with a coating of pressure sensitive adhesive, generally indicated by reference character 19.

In the step shown in FIGURE 2, the vinyl sheet 16 together with adhesive coating 19 has been Iadhered to the surface 14 of the base 13, following which a layer of polyvinyl foam 26 has been juxtaposed to leave the npper surface 27 exposed, and the lower surface 28 in contact with the upper surface 17 of the vinyl sheet 16.

Referring to FIGURE 3, .the assembled components shown in FIGURE 2 are then subjected to the action of a heated die 29 having a plurality of edges 30. As best seen in FIGURE 4, the edges 30 are of a tapered configuration which simultaneously cuts and fuses the foam layer 26 and the vinyl sheet layer 16 over predetermined areas corresponding to the shape of the pads to be formed, thereby sealing the upper surface 26 of the vinyl sheet member to the upper surface 27 of the Vinyl foam layer 26. This operation forms a plurality of pads, generally indicated'by reference character 31.

In lthe final step seen in FIGURE 5, the remaining portions of the foam rubber layer 26 and the vinyl sheet layer 16 are stripped from the base 13, leaving the assembled pads in situ, so that the same may be readily removed by the ultimate user as seen in FIGURE 6. During this removal, the foam rubber layer will part from the lamination without difliculty, owing to the fact that it is completely severed from the formed pads 31, while the remaining portions of the vinyl sheet layer 16 must be pulled against the action of the unused pressure sensitive adhesive layer 19, whichwas originally coated over the entire lower surface 18.

Referring to FIGURE 7, there may be seen a completed pad 31, including a base portion 40, a foam portion 41 and adhesive portion 42. The upper surface 43 of the foam layer 41 is of generally rounded contour, with a complete absence of sharp edges which may engage another object during movement parallel to the plane of the base portion 40. This contour is the result of the simultaneous cutting and fusing action caused by the die 29 which is -arranged by means (not shown) which permit the same only to reach the upper surface 14 of the base 13, without being permitted to cut through the same.

I wish it to be understood that I do not consider the invention limited to the precise details of structure shown and set forth in this specification, for obvious modcations will occur to those skilled in the art to which the mvention pertains.

I claim:

1. The method of forming a resilient pad from heat seal-able materials comprising the steps of: providing a first lamina of material having a calendered surface; prooperation in com- -Patented Feb. 6, 1962V viding a second lamina of flexible heat scalable synthetic resinous material; laminating said first and second laminae using a pressure sensitive adhesive; providing a third lamin a of synthetic resinous foam material which is heat sealable with respect to said second lamina; placing said third lamina in superimposed position upon the exposed surface of said second lamina; cutting pads from said third lamina and simultaneously heat sealing the peripheral edges thereof to the adjacent surface of said second lamina; removing the unsealed portions of said third lamina from contact with said second lamina, and; stripping the remaining portions of said second lamina from contact with said first lafmin-a.

2. Themethod of forming a resilient pad from heat scalable materials comprising the steps of: providing a first lamina of material having a calendered surface; providing a second lamina of exible heat scalable synthetic resinous material; laminating said first and second laminae using a pressure sensitive adhesive; providing a third lamina, of synthetic resinous foam material which is heat scalable with respect to said second lamina; placing saidV third lamina in superimposedY position upon the exposed surface of said second lamina; cutting pads from said References Cited in the file of this patent UNITED STATES PATENTS Y Alderfer Peb. 22, 1955 2,702,769 2,712,311 Scholl ....1 .lu-ly 5, 1955 2,716,625 Scholl Aug. 30. `1955 2,878,153 Hacklander Mar. 17, 1959 2,904,814 Scholl Sept. 22, 1959 2,917,846

Scholl Dec. 22, 1959 

1. THE METHOD OF FORMING A RESILIENT PAD FROM HEAT SEALABLE MATERIALS COMPRISING THE STEPS OF: PROVIDING A FIRST LAMINA OF MATERIAL HAVING A CALENDERED SURFACE; PROVIDING A SECOND LAMINA OF FLEXIBLE HEAT SEALED SYNTHETIC RESINOUS MATERIAL; LAMINATING SAID FIRST AND SECOND LAMINAE USING A PERSSURE SENSITIVE ADHEAIVE; PROVIDING A THIRD LAMINA OF SYNTHETIC RESINOUS FOAM MATERIAL WHICH IS HEAT SEALABLE WITH RESPECT TO SAID SECOND LAMINA; PLACING SAID THIRD LAMINA IN SUPERIMPOSED POSITIONS UPON THE EXPOSED SURFACE OF SAID SECOND LAMINA; CUTTING PADS FROM SAID THIRD LAMINA AND SIMULTANEOUSLY HEAT SEALING THE PERIPHERAL EDGES THEREOF TO THE ADJACENT SURFACE OF SAID SECOND LAMINA; REMOVING THE UNSEALED PORTIONS OF SAID THIRD LAMINA FROM CONTACT WITH SAID SECOND LAMINA, AND;STRIPPING THE REMAINING PORTIONS OF SAID SECOND LAMINA FROM CONTACT WITH SAID FIRST LAMINA. 